Polyembryony, Biology

Assignment Help:

Polyembryony

Presence of more than one embryo in a seed is termed polyembryony. The phenomenon, first discovered in orange seeds by Leeuwenhoek (1719), attracted considerable attention because of its potential for application in and horticulture. Polyembryony is broadly classified into simple and multiple, depending on whether the supernumerary arises in one or more embryo sacs in the ovule. Simple polyembryony may be sexual or asexual. In sexual polyembryony embryos may originate from the fertilized egg and synergids, or by budding or cleavage of the polyembryony cells or suspensor of the zygotic embryo.

Asexual embryos are produced within the embryo sac without fertilization. Embryos may also originate from diploid nucellar or integumentary cells of the ode and grow into the embryo sac. These embryos are termed adventive or sporophytic. Multiple polyembryonies involve production of accessory embryos from two or more embryo sacs in the same ovule. For example, in the sea Island cotton, Gossypium barbadense, fertilization of egg in one embryo sac stimulates the induction of embryo from an unfertilized egg in the adjacent embryo sac within the same ovule. Thus, diploid-haploid twin embryos are produced in the seed.


Related Discussions:- Polyembryony

Use of neurotensin in consciousness, Q. Use of Neurotensin in consciousness...

Q. Use of Neurotensin in consciousness? Although little is known about the role of this peptide during the sleep-wake cycle, it has recently been shown that neurotensin injecti

Define amylopectin - carbohydrates, Define Amylopectin - carbohydrates? ...

Define Amylopectin - carbohydrates? Amylopectin differs from amylose in being highly branched. Short side chains of about 30 glucose units are attached with α (1-6) linkages ap

Excretion, What is d excretory organ of the agama lizard

What is d excretory organ of the agama lizard

Explain oleic - linoleic fats, Oleic - Linoleic Fats Fats in this grou...

Oleic - Linoleic Fats Fats in this group are the most abundant. The oils are all of vegetable origin and contain large amounts of oleic and linoleic acids, and less than 20%

The cell, how does autophagy help in converting a tadpole larva into an adu...

how does autophagy help in converting a tadpole larva into an adult amphibian

Explain absorption and metabolism of minerals, Explain Absorption and Metab...

Explain Absorption and Metabolism of Minerals? All minerals in the diet are not equally absorbed. Also different compounds and complexes of same mineral are absorbed with diffe

Etiologic factor of congestive cardiac failure, Q. Etiologic factor of Cong...

Q. Etiologic factor of Congestive Cardiac Failure? Congestive heart failure develops over a period of time when the necrotic tissues are not replaced by functional connective c

Explain amylose, Amylose Amylose molecules have molecular weights rangi...

Amylose Amylose molecules have molecular weights ranging from 10 4 -20 6 . Amylose can form an extended shape (hydrodynamic radius 7-22 nm) but generally tends to wind up into

Blood clotting, BLOO D CLOTTING - It is a nature's device to check ...

BLOO D CLOTTING - It is a nature's device to check the excessive loss of blood from an injury. Bleeding time is 1-3 minutes. Clotting time is 2-6 minutes. Process of

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd